Limitations of applying summary results of clinical trials to individual patients: the need for risk stratification.

Institute for Clinical Research and Health Policy Studies, Tufts-New England Medical Center, Boston, Massachusetts 02111, USA.
JAMA The Journal of the American Medical Association (Impact Factor: 30.39). 10/2007; 298(10):1209-12. DOI: 10.1001/jama.298.10.1209
Source: PubMed

ABSTRACT There is growing awareness that the results of randomized clinical trials might not apply in a straightforward way to individual patients, even those within the trial. Although randomization theoretically ensures the comparability of treatment groups overall, there remain important differences between individuals in each treatment group that can dramatically affect the likelihood of benefiting from or being harmed by a therapy.1- 4 Averaging effects across such different patients can give misleading results to physicians who care for individual, not average, patients.

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